1. Field of the Invention
This invention relates to methods and apparatus for correlating rotational and translational motions, and, more specifically, to methods and apparatus for correlating the rotation of a linear polarization analyzer with the precise and accurate linear translation of a moveable mirror.
2. Brief Description of the Prior Art
There are many circumstances or situations in which it is desirable to measure and control very accurately and precisely the angular rotation or the linear translation of one or more objects. Numerous laser apparatus, which produce intense beams of coherent monochromatic light, have been used quite successfully for relatively accurate detection and alignment applications. Unfortunately, however, there is a need for even more accurate measuring and control capability to detect and control even more minute changes than possible with present laser and other devices for many applications, including improving the performance of interferometers, optical nanolithography for manufacturing semiconductor components, and for providing accurate, step-wise rotational control for fabricating circular optical encoders.